How does this medication work? What will it do for me?

Nevirapine belongs to the class of antiretroviral medications called non-nucleoside reverse transcriptase inhibitors (NNRTIs). It is used in combination with other antiretroviral medications to treat the infection caused by the human immunodeficiency virus (HIV).

HIV is the virus responsible for acquired immune deficiency syndrome (AIDS). HIV infection destroys CD4 (T) cells, which are important to the immune system. The immune system helps fight infections.

Reverse transcriptase is a part of HIV required to infect cells and make more virus. Nevirapine prevents reverse transcriptase from working properly.

Nevirapine does not cure AIDS and does not prevent it from being spread to others. It helps to slow down further growth or reproduction of HIV when used in combination with other medications. It also seems to slow down the destruction of the immune system. This may help to delay the development of problems that are related to AIDS or HIV disease.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

How should I use this medication?

The recommended adult dose of nevirapine is 200 mg once a day for the first 2 weeks, and then 200 mg twice a day (every 12 hours) or 1 tablet of 400 mg extended release nevirapine once a day (every 24 hours) after the initial 2 weeks. Your doctor may decide on a different dosing pattern. Do not change your dose unless instructed by your doctor. The initial dose of 200 mg once daily helps to reduce the risk of rash that may develop with use of nevirapine. If you do develop a rash while taking this medication, call your doctor for further instruction.

This medication may be taken with or without food. Do not crush or chew the extended release tablets.

It is important to take this medication exactly as prescribed by your doctor. The effectiveness of the medicine depends on maintaining the right amount of nevirapine in the bloodstream. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice. If you miss many doses in a row, talk to your doctor about how to resume dosing.

If you have been asked to stop taking the medication for more than a 7-day period, your doctor will likely have you start taking only one 200 mg tablet daily for the first 14 days and then increase to 200 mg twice daily after that.

Store nevirapine tablets at room temperature and protect them from excessive light and moisture. Keep the bottle tightly closed and out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not take nevirapine if you:

are allergic to nevirapine or any ingredients of this medication

have needed to stop taking the medication due to severe rash, allergic reactions, or hepatitis caused by nevirapine

have severely reduced liver function

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

abdominal or stomach pain

diarrhea

headache

nausea

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

aching joints and muscles

increased fat on the upper back, neck, breasts, and around the trunk; and loss of fat from the legs, arms, and face

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

Birth control: Nevirapine may reduce the effectiveness of birth control pills. Use another form of birth control if taking this medication.

Fat redistribution: Over time, this medication may change how fat is distributed in your body and may change your body shape. You may notice increased fat in the upper back and neck, breast, around the back, chest, and stomach area; or loss of fat from the legs, arms, and face. The long-term effects of this are not known.

Immune reconstitution syndrome: This medication may cause immune reconstitution syndrome, where signs and symptoms of inflammation from previous infections appear. These symptoms occur soon after starting anti-HIV medication and can vary. They are thought to occur as a result of the immune system improving and being able to fight infections that have been present without symptoms (such as pneumonia, herpes, or tuberculosis). Report any new symptoms to your doctor as soon as possible.

Kidney function: If you have reduced kidney function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. People with severely reduced kidney function should not take this medication.

Liver damage: This medication may cause liver damage. The risk is highest during the first 6 weeks of treatment. Women are also more likely than men to experience liver damage when taking nevirapine. Anyone who had CD4+ counts of over 250 cells/mm³ when treatment was started are at a higher risk, but anyone taking this medication may be at risk of liver damage.

Your doctor will order regular blood tests to watch for early signs of liver damage. Stop using this medication and contact your doctor as soon as possible if you notice any symptoms of liver damage, including unusual tiredness or weakness, abdominal pain, loss of appetite, or jaundice (yellow eyes or skin).

Liver function: Nevirapine is broken down by the liver so it can be removed from the body through the kidneys. Liver disease or reduced liver function may cause a build-up of nevirapine in the body and cause side effects.

If you have liver disease or decreased liver function, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Skin reactions: Nevirapine can cause a severe form of skin reaction that may be life threatening. This is most likely to occur in the first 6 weeks of taking this medication. If you experience a severe rash or a rash at the same time as fever, feeling generally unwell, blisters, muscle or joint aches, contact your doctor or get medical attention immediately.

Pregnancy: Adequate studies on the use of this medication by pregnant women are not available. Talk to your doctor for guidance.

Breast-feeding: It is not known if nevirapine passes into breast milk. Women who have HIV infection are cautioned against breast-feeding because of the risk of passing HIV to a baby who does not have the infection.

Children: The safety and effectiveness of this medication have not been established for those less than 15 years of age.

What other drugs could interact with this medication?

There may be an interaction between nevirapine and any of the following:

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

stop taking one of the medications,

change one of the medications to another,

change how you are taking one or both of the medications, or

leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.